The present invention relates to fermentation aids for conventional Saccharomyces cereviseae yeast raised baked goods and particularly bread.
Fermentation, in the manufacture of bread, in addition to gas formation performs numerous important functions such as dough conditioning and flavor development. The gluten, tough and elastic after hydration, is developed or conditioned during the fermentation stage to make the dough soft and pliable. This is accomplished by enzymes and reducing agents in the yeast and also by the stretching of the gluten by the gas formed during fermentation. The correct amount of conditioning is important in making good bread. Underdeveloped gluten causes poor volume and texture, faster staling and reduced shelf life. Overdeveloped gluten becomes too weak for good bread characteristics. It is essential that the gluten form an optimally soft and elastic network to trap the gas developed during fermentation, and expand to optimum volume.
The development of flavor and aroma components is also a critical function of the fermentation. The development of these components is favored by long-term fermentations.
Traditional processes of bread making involve long fermentation times. One such process is the straight dough process. In this process, all the ingredients of the bread are added at the initial mixing stage, mixed into a dough and fermented for a relatively long period of time allowing for maximum acceptable dough conditioning and the proper development of flavors and aromas. A variation of this basic process is the "Sponge and Dough" process. In this process part of the flour, yeast, yeast food and part of the water are mixed initially into a dough-like sponge. This sponge is allowed to ferment for about 3 to about 4 hours (from about 82% to about 93% of the total fermentation time). The remainder of the dough ingredients is then added to the sponge to form a dough which is then allowed to ferment for about 20 to about 40 minutes (the balance of the total fermentation time). This process accounts for a large proportion of the bread prepared in the United States and gives a good quality loaf.
However, long fermentations are expensive as they are time and labor consuming, require large fermentation areas and also skilled supervisory personnel.
Numerous methods have been developed to shorten the fermentation time. Prominent amongst these short time methods are high yeast and high dough temperature methods; continuous mix methods, high speed mixing methods and variations and combinations of the above.
While the use of additional yeast and higher temperatures can speed up the fermentation, this is generally at the expense of flavor, aroma and texture since sufficient time has not been allowed for their development. Further, the use of high temperature and/or high yeast levels minimizes process tolerance limits.
Another process for preparing bread involves the complete elimination of fermentation. In this process called the continous dough process, all the ingredients are added into a high speed mixer known as a developer. Here the conditioning of the gluten which is normally carried out over an extended period of time is accomplished within a very short time by means of the input of work by high speed rotors. The result is the complete elimination of fermentation time, and the formation of a loaf of bread of good symetrical qualities when viewed from the outside. However, the characteristic flavor and aroma of fermented bread is absent and there is a difference in the bread texture which can be characterized as "short-eating" instead of the characteristic chewy bread mouth feel of conventional fermented bread.
In another process, termed liquid ferment breadmaking, fermentation is conducted in a liquid before enough flour to make a dough has been added. The fermentation broth contains water, yeast, sugar, enrichment nutrients and yeast food and optionally a portion of the flour. The liquid ferment, flour, shortening, additional sugar and an oxidizing agent are then pumped to a developer where rapidly rotating agitators develop the dough. The dough is then cut, shaped, proofed and baked. In this process, some of the fermentation flavors and aromas can be introduced into the bread as a result of the liquid ferment. However, some reservations have been expressed about the bread texture as developed by high speed mixing vis-a-vis dough fermentation.
The time for fermentation is especially acute in the preparation of sour dough. Sour dough relies upon the formation of lactic acid by a specific lactobacillus, L. sanfrancisco, and the fermenting of a special yeast, T. holmii to form a bread having the characteristic sour dough taste (U.S. Pat. No. 3,894,773). The original method of manufacturing sour dough was to innoculate a new dough with a piece of fermented dough which thus provided the lactobacillus and the yeast. Generally 8-12 hours of fermentation is needed to adequately develop the flavor.
Numerous patents exist which are directed to processes for reducing the fermentation time while providing the desirable sour dough flavor. In general, these patents relate to prefermenting a base with a lactobacillus to form lactic acid which, alone or in combination with T. holmii, is added directly to the dough. By these procedures, an initial start is given to the lactic bacteria thus reducing fermentation time. These preferments can be freeze dried to prevent destruction of bacteria or spray dried (kills the yeast).
Sour dough bread is well known in the industry as a bread having specific flavors and production problems. Sour dough bread is distinct from other breads which are raised with a yeast of the genus Saccharomyces, i.e. non-sour dough bread. None of the aforementioned references teaches a method for reduction in the fermentation time of conventional baked goods such as American white, natural or variety breads. While fermentation time in conventional baked goods can be reduced by such means as the use of excess yeast and higher temperature, the decrease in the fermentation time has been at the loss of dough conditioning and texture as well as the necessary flavor and aroma components needed for good results.